This invention relates to a compact, easy to assemble, low cost paper shredder.
In order to destroy documents to preserve their confidentiality, commercial shredders exist which cut the paper into narrow strips. Typically, the cutting is achieved by a series of circular cutters which are arranged along the axis of two rotating members. The cutters of one rotating member are offset so that the cutters pass between the cutters of the other member.
The actual structure of the rotating members having cutters can be a solid bar of steel or similar material in which cutters and spacers are formed by machining so that the cutters and spacers are all integral to one another. Another structure has separate cylindrical members of a large diameter which are used as the cutters and are spaced apart by separate cylindrical spacers which are assembled on a shaft in an alternating relationship.
The problem with these shredding devices is that the shaft must be mounted on bearing plates within the housing. This requires assembly of a number of parts and fasteners. The present invention solves these problems by providing molded bearing plates integral to the inside surfaces of the housing. Therefore, no parts or assembly is required to mount the shafts.
Another problem with known and existing shredding devices is that after the paper has been cut into strips, the strips tend to wind around the cutters and spacers, clogging the cutting area. To solve this problem it has been suggested to provide a stripping means to strip away the cut paper. Typically, the stripping means consist of a serrated member or a comb type member having teeth which protrude in the spaces between the individual cutters. These members are located on the outward or post-shredder side of the cutting area.
For example, U.S. Pat. No. 4,068,805 shows a comb means rigidly placed at the exit of the cutters and extending into at least one of the cutters.
Another method of providing a stripping means is shown in U.S. Pat. No. 3,033,064 which discloses a pair of combs each having a series of spaced teeth that project into the spaces between the cutters to remove the cut strips of paper. Each comb is rigidly mounted so that the teeth protrude into the side of the cutter shaft opposite of the cutting area. In addition, they are formed in a semi-circular shape so that they wrap around the series of cutters.
In addition, it has been suggested to provide a comb type member before the cutters. The comb then guides the uncut paper into the cutters. U.S. Pat. No. 4,018,392 shows a pair of combers attached to support rods, each comber having a tongue protruding forward of the cutters to comb and direct the material being fed to the cutting surfaces of the cutters.
The problem with these shredders and others is that a number of individual parts are required. Separate parts are required for the comb assembly and for mounting to the shredder housing. This increases the time and labor required to assemble the shredder which in turn increases the cost of the shredder. Therefore, the present invention is directed to a paper shredder that has few parts and is easy to assemble. This will result in a paper shredder that has a lower cost than conventional paper shredders.